(HealthDay News) — Currently available antibodies for the excision repair cross-complementation group 1 (ERCC1) protein are not adequate for therapeutic decision-making regarding the potential efficacy of cisplatin-containing treatment in patients with non-small-cell lung cancer, according to a study published the March 21 issue of the New England Journal of Medicine.
Luc Friboulet, Ph.D., from University of Paris, used the 8F1 antibody to measure the level of expression of ERCC1 protein using immunohistochemical analysis in a validation set of 499 patient samples obtained from two independent phase 3 trials.
The researchers were unable to validate the predictive effect of immunostaining for ERCC1 protein. They found discordance in staining for ERCC1 suggestive of a change in the performance of the 8F1 antibody since 2006, when an initial correlation between the absence of ERCC1 expression and platinum response was identified. None of the 16 antibodies could distinguish among the four ERCC1 protein isoforms. A protein capable of nucleotide excision repair and cisplatin resistance was only produced by one isoform.
“Immunohistochemical analysis with the use of currently available ERCC1 antibodies did not specifically detect the unique functional ERCC1 isoform,” the authors write.
Eli Lilly funded the study.